1. Field of the Invention
The present invention relates to a wheel motor device including a hydraulic motor unit for operatively driving a corresponding driving wheel.
2. Related Art
A wheel motor device provided in a vehicle so as to independently drive a corresponding driving wheel has been conventionally known (for example, see Japanese unexamined patent publication No. 2006-96112).
Since the wheel motor device can be arranged close to the corresponding driving wheel, a free space could be secured between a pair of driving wheels and a degree of design freedom of the vehicle could be enhanced compared to a transaxle-driving device including a differential gear device for differentially connecting the pair of driving axle.
However, with the conventional configuration, it is needed to independently attach the wheel motor device and a hydraulic pump main body, which cooperates with a hydraulic motor main body in the wheel motor device, to a vehicle main body, and then fluidly connect the hydraulic motor main body and the hydraulic pump main body by an external conduit, in the assembly work to the vehicle main body, resulting in worse assembly workability and worse piping workability.
Furthermore, it is desirable to perform adjustment work of a traveling hydrostatic transmission (HST) configured by the hydraulic motor main body and the hydraulic pump main body in a state where the hydraulic motor main body and the hydraulic pump main body are fluidly connected to each other with a condition corresponding to a vehicle-mounted condition where they are mounted to the vehicle main body. However, with the conventional configuration, such adjustment work could not be performed unless the wheel motor device and the hydraulic pump main body are actually attached to the vehicle main body.